goffin



UNITE@ STATES PATENT QFFIQE.

F. C. GOFFIN, OF NFV YORK, N. Y.

LOCK.

Specification of Letters Patent No. 9,1361, dated October 26, 1852.

To all whom it may concern.'

Be it known that I, F. C. GOFFIN, of the city, county, and State of New Yfork, have invented a new and Impro-ved Lock for Safes, Bank-Vaults, &c.; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making a part of this specification, in which- Figure l, is a. front view of the lock. Fig. 2, is a side view of ditto, the side plate being removed in order to show the interior. This view shows the position of the tumblers, lever, and guard when the bolt is thrown out or the door locked. Fig. 3, is also a side view of ditto, the red lines indicating the position of the several parts above mentioned when the bolt is withdrawn or the door unlocked. The black lines showing t-he lever, and guard, thrown back or freed from the tumblers, so that they (the tumblers) may be operated upon by the key. Fig. 4, is a. back view of the lock, one of the side pla-tes being removed. F ig. 5, is a view of the key of the lock.

Similar letters of reference indicate corresponding parts in each of the several figures.

The nature of my invention consists in the employment or use of a guard, which with the lever, which intercepts the bolt or prevents it from being withdrawn, rests 0r bears upon the tumblers, said guard requiring to be freed from the tumblers as well as the lever, before the tumblers can be adjusted by the key so as to allow the lever to fall into the recesses in the tumblers, and enable the bolt to be withdrawn. By this arrangement, as will be present-ly shown the lock can not be picked, because the lever which acts upon the bolt does not bear singly or alone upon the tumblers, and the method of picking locks hitherto adopted by burglars7 viz., by obtaining a pressure upon the bolt, is by my improvement rendered utterly impossible.

To enable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A, represent a series of tumblers of sector form, any number may be used, they are placed side by side as usual and have a common axis (a) only one tumbler is seen in Fig. 2, this one is suflicient as they are a. well known device and are in common use.

Each tumbler has a recess (b) in it, andl these recesses are placed at different distances uponthe sectors, so that each tumbler must be turned or moved a certain distance varying from the others in order to bring the recesses (Z2) of the different tumblers in line.

B, is a lever having its fulcrum at On the upper part of this lever B, there is a` pawl (cl) which bears against the edges of the tumblers, see Figs. 2, and 3, and eX- tends the whole breadth of the tumblers, see dotted lines in Fig. 4L. The edges of the tumblers are toot-hed a certain distance o-n their edges, and this pawl (d) catches into those. teeth as seen in Fig. 2. The lower end of the lever B, is directly back of the bolt C, that is, when the bolt is thrown forward and the door locked as seen in Fig. 4, and in order to withdraw the bolt C, the lower end of the lever B, must be thrown backward so that the bolt can pass between the lower end of the lever B, and the door see red lines in Fig. 3. The lever or rather the pawl (d) of the lever is kept against the teeth of the tumblers by means of a spring (e).

The recesses of the tumblers A, being as before stated at dilerent points upon the tumblers, and as each tumbler in consequence requires to be moved a certain distance differingfrom the others, in order to bring the different recesses in line, a key D, is employed terminating in prongs of unequal lengths and corresponding to the different distances of the recesses in the tumblers. Now when these prongs are pressed upon the tumblers at (f) through av slot in the door, the recesses (b) are brought in line and the pawl (cl) falls into the recesses and the lower end of the lever B, is thrown backward the spring (e) acting upon the lever and the bolt allowed to pass between the lower end of the lever and the door. See red lines Fig. 3. l Before however the tumblers A, can be moved by the key D, the pawl (el) must be freed fr0-m the teeth of the sectors. This is done by the rod E, the end of which bears against the upper part of the lever B. By passing this rod inward the upper part of the lever is thrown backward and the pawl (d) thrown from the teeth of the tumblers, when the rod E, is pressed inward it is kept so by turning the escutcheons G, upward till it passes over the outer end of the rod. The key is then ap* a spring (g) at its upper part.

plied to the tumblers as before mentioned. To lock the door the bolt is t-hrown forward by means of the ordinary knob (not represented) and the escutcheon turned Clownward to its original position, the spring (c) then throws the upper part of the lever forward and the pawl (d) into the teeth of the tumblers, the lower end of the lever B, passing behind the end of the bolt and the door is secured. Each tumbler is provided with These springs throw the tumblers into their original position when relieved from the pressure of the key.

F, is the guard which is on the pivot C, which serves as the fulcrum of the lever B. The guard is provided with a spring (7L) similar to the spring (e) of the lever B. The guard also has a pawl which catches into the teeth of the tumblers A. The guard it will be seen acts upon the tumblers similar to the lever B, but independently of it. Its use will now be explained.

If there were no guard the lock could be picked by merely pressing the rod E, a little inward so that the teeth of the tumblers may be free from the guard and pawl and then by operating each tumbler separately the position of the different recesses in the several tumblers could be ascertained by the sense of feeling. This is the great secret of lock picking. The guard F, it will be seen effectually prevents this, because both pawls (d) catch into the teeth of the tumblers and when the pawl (d) of the lever B, is opposite a slot in one of the tumblers the pawl of the guard is between the teeth of the tumbler just above the slot, consequently the sense of feeling is precisely the same whether the pawl (d) is opposite a slot or not. This will be readily understood. The inner end of the rod E, when pressed inward throws back the guard and its pawl (i) from the teeth of the tumblers as well as the lever B, ,and its pawl Y Another mode of opening locks practised by burglars is to drill a hole through the front plate and by means of small tools operate upon the tumblers and ascertain the position of the slots. This is efectually prevented by placing or arranging the tumblers as follows. The ivot or axis (a) of the tumblers is placed iorizontally, and the tumblers consequently hang perpendicularly on the axis or pivot (a). The pawls (d) of the lever B, and the guard F, are on the inner or face side of the tumblers at a point farthest from the front plate of the lock. Consequently the pawls cannot be reached by drilling as the whole length of the tumbler would have to be pierced before reaching the necessary parts, (the pawls) neither can the position of the slots (b) be ascertained as will be readily seen.

Locksmiths at present have a steel or hardened iron plate over the cap of their locks to prevent drilling, but burglars often soften these by heat and succeed in drilling through them.

I do not claim the tumblers A, or the lever B` for they are employed in many locks and have been long known, but

lVhat I claim as my invention and desire to secure by Letters Patent, is,

The employment or use of a guard F, constructed, arranged, and operating in the manner substantially as herein described whereby the lock is prevented from being picked by obtaining a pressure upon the bolt as set forth.

F. C. GOFFIN. Witnesses:

O. D. MUNN, S. H. WALES. 

